Lecture 14: Metabolic Reactions and Enzymes

1. What are four examples of the use of energy in the cell?

1. Moving within the cell (meiosis/mitosis)

2. The entire cell moving

3. Making concentration gradient (active transport; osmosis)

4. Building large macromolecules

1. Describe a catabolic reaction and what reaction is it similar to?

1. Complex molecules being broken down into simple molecules

2. Exergonic reaction

1. How is hydrolysis an example of a catabolic reaction?

It breaks down two monosaccharides by inputting H2O.

Describe an anabolic reaction and what reaction it is similar to?

1. Simple molecules form more complex molecules

2. Endergonic reaction

1. It is difficult to move polar covalent bonds because there is ____ potential energy.

Less

1. T/F: Nonpolar means there is equal electron sharing.

True

Glucose is a rich source of potential energy

True

1. There is most potential energy in ______ bonds.

Nonpolar

Glucose is originally in the most (reduced/oxidized) state

1. Reduced (has lots of electrons)

1. The electron carrier for glucose, NAD+, is ___ to form NADH.

Reduced

Molecules in the most reduced state have the most ___/potential energ

Free

1. ATP becomes ADP through the process of _____. This is an ______ reaction.

Hydrolysis; exergonic

What are the sources of energy that are used to form ATP from ADP?

Exergonic reactions such as cell respiration and catabolism

1. ATP Hydrolysis is coupled to ______ reactions.

Endergonic

1.  ATP hydrolysis + endergonic reaction coupled together are exergonic.

true

saturation

The number of active sites is important, because ______ of enzymes can occur due to excess substrate.

What are competitive inhibitors?

They actively block the binding sites themselves to prevent substrates from binding. They’re temporary inhibitors.

1. Allosteric regulation is different from competitive inhibition because?

It changes the shape of an enzyme entirely rather than temporarily binding to a site.

1. What are two types of allosteric regulators?

1. Activators and inhibitors - kind of self-explanatory, but Activator allows active sites to become available to substrates when a regulatory molecule binds to a different site. Inhibitor is the opposite - the active site becomes unavailable when a regulatory molecule binds to a different site.